The analytical theory describing magnetostatic oscillations in a transversely magnetized infinitely long ferromagnetic cylinder of elliptic cross-section has been developed. The implicit equation for the eigenfrequencies of modes has been derived and analyzed. An example of frequency spectrum of an elliptic cylinder with a/b=2 was presented. Magnetostatic potential of the eigenmodes in form of elementary functions has been found, that will allow obtaining simple analytical expressions for spatial distribution of the high-frequency magnetization.